Chris Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

I'm willing to believe that structures and TPS and other parts of the vehicle can be designed and built to require only minimal, economic amounts of refurb between flights.

Turning your point around please prove out how you've reached the conclusion that TPS and structures can be designed and built to require only minimal, economic amounts of refurb between flights.

In particular, how does one asses and ensure the life of these components? How does one optimize their processing to deal with something such as micrometeorite and orbital debris impacts?

It is an unproven assertion so far.

SpaceX has quite a track record at this point of taking previously difficult, expensive and time consuming tasks (rocket engine refurb, capsule heat shield construction) and re-engineering them into reliable, inexpensive solutions. I suspect that this is the case because they actually set out to make things into reliable, inexpensive solutions.

We'll just have to wait and see how difficult this ends up being for the TPS on BFS.

Dragon is a good analogy actually.. same diameter, similar mass, a little shorter... S2 has avionics...

Will require moving the cg and center of drag, adding heat shield, maybe dropping the large nozzle.

None of these are against the laws of physics or even of common sense engineering.

It's just that there are finite engineering resources, and BFS is front burner now.